One problem that is constantly experienced in clearing bushes, shrubs and trees, particularly of cedar and juniper plant species, from cultivated or pasture lands is the ease with which such plant species can re-grow when their root portion is left in the ground. Accordingly, the root portion of such plant species must be extracted from the ground in order to minimize the re-growth. Another problem is related to reduction of the contact area of the clearing equipment with the surrounding soil in order to minimize soil disturbance and preserve valuable grass covering surrounding such plant species.
Efforts have been made to alleviate problems of extracting cedar and juniper plant species. U.S. Pat. No. 5,901,477 issued to Weaver discloses a tree removing device which is designed for mounting on a land vehicle such as a conventional bulldozer or tractor and has a bulldozer-type extracting device fitted with a power extractor for cutting the roots of a tree and a tree jack for levering the tree from the ground after the roots are cut.
The power extractor is characterized by a frame pivoted to the bulldozer-type extracting device and a vertically adjustable carrier mounted in the frame and internally fitted with a hydraulically operated extractor which may be extended into the ground from the carrier to cut the roots of a tree by operation of the land vehicle.
The tree jack includes a jack frame pivoted to the land vehicle bulldozer-type extracting device and a mast attached to the jack frame, which jack frame is fitted at one end with a foot for engaging the tree. The mast includes hydraulic cylinders for both engaging the tree and causing the mast to pivot, thereby jacking the tree from the earth by operation of the jack frame foot. However, the use of hydraulically operated extractor and mast and their support structures increases the manufacturing and maintenance costs and reduces the reliability of the device.
U.S. Pat. No. 5,111,599 issued to DeSalvo et al discloses an implement for uprooting and removing bushes and small trees from pasture land. The device is adapted to be mounted on a tractor having a front end loader assembly and includes a transverse horizontal bar having tooth like projections along its leading edge. The teeth are long and reinforced for greater strength.
Channels are defined by the teeth and shaped to provide narrow openings at the roots of the teeth to grasp small bushes. The wider mouth of each channel between teeth will accommodate larger stems or trunks. Brush is conveniently uprooted and transported by the tractor mounted device. While providing a simpler and more reliable apparatus, DeSalvo failed to resolve the problem of reducing the contact area in order to preserve valuable grass covering surrounding such plant species.